1. Field of the Invention
The present invention relates to a method of manufacturing a piezoelectric vibrator element.
2. Description of the Related Art
For example, in the electronic apparatus such as a cellular phone or a portable information terminal, there is used a piezoelectric vibrator using a quartz crystal or the like as a device used for a clock time source, a timing source for a control signal and so on, a reference signal source, and so on. As a piezoelectric vibrator of this kind, there has been known a device having a piezoelectric vibrator element hermetically encapsulated in a package provided with a cavity. In recent years, a demand for miniaturization of the piezoelectric vibrator and the piezoelectric vibrator element is more and more increasing due to the miniaturization of the electronic device.
As described in, for example, JP-A-2009-194630 (Document 1), a plurality of piezoelectric vibrator elements are manufactured in a lump using a wafer made of a piezoelectric material. On this occasion, the piezoelectric vibrator elements are formed in the state of being connected to a frame part for supporting a piezoelectric plate via connection parts. On one principal surface of the wafer, a pair of extending electrodes extending from the piezoelectric plate to the frame part passing through the connection parts are formed so as to correspond to the respective piezoelectric vibrator elements. The frequency of each of the piezoelectric vibrator elements is measured by, for example, pressing a probe or the like against the extending electrode on the frame part. Subsequently, the piezoelectric vibrator elements are cut in the connection parts to be segmentallized.
Incidentally, in the piezoelectric vibrator element, the strength of each part of the piezoelectric vibrator element decreases in some cases due to the miniaturization of the piezoelectric vibrator element. Therefore, there is a possibility that the piezoelectric vibrator element is damaged due to the stress acting via the connection part when segmentallizing the piezoelectric vibrator element. Therefore, it is desirable for the connection part to be formed smaller in width so as to be able to be cut easily.
However, in the related art, since the pair of extending electrodes are formed on the one principal surface of the connection part so as to be arranged side by side, there is a limitation to narrow the width of the connection part while preventing the short circuit between the pair of extending electrodes on the grounds of the accuracy of patterning of the extending electrodes. Therefore, in the method of manufacturing the piezoelectric vibrator element in the related art, there is a problem regarding the point of preventing the piezoelectric vibrator element from being damaged when segmentallizing the piezoelectric vibrator element while miniaturizing the piezoelectric vibrator element.